Tear away opening for multi-layer plastic pack
A tearable closure and a container with a tearable closure is disclosed. The tearable closure includes non-penetrating perforations or score lines in and across the tearable closure on a first side, and has continuous film material on the second side. Such tearable closure can be incorporated into one of numerous types of containers, including envelopes, boxes, and bags. The tearable closure can be a flap, a lid, or a tape.
The present invention is related to opening mechanisms for opening sealed containers, including multi-layer plastic packs, such as envelopes used by overnight or express mail delivery services.
BACKGROUND OF THE INVENTIONPackages that are sent from a sender to a receiver will require opening by the receiver. Many packages come with a flap that can be folded over to seal the package opening. Packages with flaps or other closures require a way of sealing the package and a way of opening the sealed package. Both sender and receiver have concerns regarding the integrity of the package during transit. Both sender and receiver are motivated to have a robust seal that will resist tearing or opening. Robust seals are typically achieved with an adhesive on the flap that bonds to the container. Lifting the flap that has been bonded to the container with an adhesive is, however, a difficult task. Accordingly, there have been many proposals for facilitating the opening of sealed packages that rely on the tearing of the flap that seals the package. Such proposals mainly rely on the use of perforations, strings, and tear strips.
The considerations for deciding which mechanism to utilize for opening packages are related to the construction materials of the package, the materials' tear properties, the complexity of manufacturing, and the associated costs.
Some users may prefer packages with robust opening mechanisms above all else, while other users may prefer the easier opening mechanisms that are nevertheless reliable enough to withstand typical handling while in transit.
While the advantages of robust opening mechanisms are evident, many of these packages involve complex or intricate manufacturing processes leading to higher prices which the consumer is less willing to accept. Examples may include strings and tear strips that are made from materials different to the flap or closure material. Strings and tear strips function by either being embedded within the flap material or by being directly adjacent to the flap, so that pulling on the string or tear strip will cause cutting or tearing of or through the flap material. Because strings and tear strips are external devices that must be integrated into the flap, manufacturing complexity is introduced.
A simpler, but more prone to inadvertent opening, is an opening mechanism that is made from the flap material itself. Perforations that completely penetrate the flap material are made along two rows to weaken the flap material along a specified narrow strip of material. It is generally regarded that such opening mechanism will sacrifice package integrity. This is because the flap is, in essence, connected to the remainder of the envelope with perhaps only as much as half of the flap material between the perforations. Furthermore, because the perforations will be visible and exposed in the exterior side of the flap, the perforations are likely starting points where, if enough pressure is applied by an object, a tear might ensue.
Accordingly, there is a need to provide an opening mechanism that given a robust seal will nevertheless be easy to open, but will be less likely to open inadvertently.
SUMMARY OF THE INVENTIONThe present invention is related to tearable closures, the containers with the tearable closures, and to methods of making tearable closures and containers. The tearable closure comprises rows of non-penetrating perforations or score lines in and across the tearable closure on a first side. The tearable closure comprises continuous film material on the second side.
One embodiment of the present invention is related to a container. The container includes a container body defining a cavity. The container body has a first and a second wall defining the front and back of the container. A flap is connected to the container body. The flap can be folded, and bonded to the container to seal the cavity. The flap includes non-penetrating perforations in the flap that are approximately from one end of the length of the flap to the opposite end of the length of the flap (length's end to length's end). The non-penetrating perforations do not cut entirely through the thickness of the flap, but are only partially cut into the flap to leave more material connecting the flap to the container than prior flaps.
Another embodiment of the present invention is related to a method for making a container with a flap. The method includes bonding a first film to a second film to produce a composite sheet. The method of making the container with the flap also includes folding the composite sheet and then bonding the two overlapped edges to form a cavity from the sheet and leaving a section of non-overlapping sheet that extends beyond the cavity that forms the flap. Non-penetrating perforations are added in the flap approximately from length's end to length's end of the flap or across the flap, and the non-penetrating perforations extend only partially into the thickness of the flap along two or more rows across the flap. A simple way to make non-penetrating perforations in the flap is to provide one film with perforations that extend through the entire thickness of the film before this film is bonded to a second film, and then bonding the perforated film to a second film which will result in non-penetrating perforations that extend only partially into the thickness of the composite sheet made from the two films. This has the advantage that precise control of the perforation depth does not have to be attempted after the bonding of the two films. The container is made so that the non-perforated film will be the exterior of the container.
Another embodiment of the present invention is related to making a container with a tearable closure. A tearable closure is any means for closing the opening of the container and there is a means in the closure for tearing the closure to open the container. The method includes forming the container and the tearable closure, wherein the tearable closure includes non-penetrating perforations that extend partially into the thickness of the tearable closure and across the tearable closure.
Another embodiment of the present invention is related to a container with a tearable closure. The tearable closure includes non-penetrating perforations that extend partially into the thickness of the tearable closure and across the tearable closure. Representative containers are envelopes, boxes and bags. Representative tearable closures are flaps, lids and tapes.
Another embodiment of the present invention is related to a tearable closure that can be incorporated into containers to facilitate opening the sealed containers. The tearable closure includes non-penetrating perforations that extend partially into the thickness of the tearable closure and across the tearable closure. Representative tearable closures are flaps, lids and tapes.
The tearable closure and container with tearable closure in accordance with the present invention have numerous advantages over the prior art means for opening sealed containers. First, the tearable closure of the invention does not need an external material to assist in tearing the tearable closure that is made from a material different to the closure material. Second, the tearable closure material is provided with non-penetrating perforations that extend partially into the thickness of the closure material and across the closure so that the perforations are not exposed and more of the flap material is remaining as compared to perforations that cut through the entire thickness of the flap. The use of a weakened closure rather than an external device eliminates manufacturing complexity and costs, and the fact that perforations do not cut through the entire thickness of the closure material decreases the likelihood that the closure will tear inadvertently.
BRIEF DESCRIPTION OF THE DRAWINGSThe foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
The present invention is related to methods of opening containers and to containers with opening mechanisms, and to the opening mechanisms. The present invention provides a tearable closure, wherein the closure can be a flap, a lid, or a tape. The tearable closure has a first side and a second side. On one side, the tearable closure has areas of reduced thickness arranged along rows or lines across the tearable closure. At least two rows or lines are present in the tearable closure so that the tearable closure will be able to tear along two of the rows or lines and thus release the tearable closure from a container to which it is attached, and thus open the container. The areas of reduced thickness in the tearable closure can be score lines that are continuous reduced areas of thickness in a line across the closure or any other part of the container, or the areas of reduced thickness in the tearable closure can be non-penetrating perforations in a row across the closure or any other part of the container. The score lines or non-penetrating perforations do not cut completely through the thickness of the closure, but are only partly cut into the closure material. By avoiding the cutting of closure material completely, the closure is strengthened, but will still be able to tear. On the side opposite to the side in which the score lines or non-penetrating perforations are provided, the tearable closure is continuous, meaning the tearable closure material is made from a continuous film material that has no areas that are of composition different to all other areas of the tearable closure. For example, if the tearable closure is made from a film material, the film material would not have areas made of fibers. The tearable closure can be connected to various containers, including envelopes, boxes, and bags to provide a means for opening the container.
Referring to
The flap 104 has a second side, wherein the first side is the side with non-penetrating perforations shown in
Nicks 112 are located in either one or both of the first and second flap sides at either one or both flap edges 132, 134. The flap material between nicks 112 produce a tab that can be pulled to initiate tearing of the flap 104 in a narrow strip of flap material that is defined between any two rows of non-penetrating perforations 110. Once the narrow strip of flap material is removed, part of the flap remains adhered to the container, and part of the flap is freed to open the container. Nicks 112 can be at an angle to the rows of non-penetrating perforations 110. According to the present invention, at least two rows of non-penetrating perforations 110 are provided in the flap so as to coincide with the end points 136 of the starting nicks 112. More than two rows of non-penetrating perforations are advantageous in the flap 104. Multiple rows have the advantage that starting nicks 112 do not have to align exactly with the rows of non-penetrating perforations 110, but allows for a small margin in error, as long as the end points 136 of the nicks 112 lie within the boundaries of rows of non-penetrating perforations 110, the angle in a starting nick 112 will cause the flap material to tear in a direction headed for one row. Once the tear reaches a row of non-penetrating perforations, the tear will follow the path of weakness which is along the row of non-penetrating perforations 110. Rows are aligned substantially parallel to each other approximately from length's end 132 to length's end 134 of the flap 104, i.e., across the flap. The non-penetrating perforations 110 are aligned along the row intermittently, therefore, in the direction of any row, the flap 104 has areas of the full flap thickness followed by areas of reduced thickness that is decreased by the depth of the non-penetrating perforation. The non-penetrating perforations 110 therefore allow tearing of that portion of the flap 104 that is bounded by two rows. The section of flap 104 that is bounded by any two or more rows is flap material and not a distinct tear strip of different material to the flap. Thus, when the flap 104 has been sealed to the container 100; pulling the area of the flap 104 between any two rows of non-penetrating perforations 110, will allow a narrow flap portion to be torn across the flap that will expose the interior of cavity 130 of the container body 102.
Referring to
In one embodiment of the invention, the container 100 is a rectangular container where length and width have been adjusted to accommodate common paper sizes. Such container is generally referred to as an “envelope.” Envelopes may come in flat or bulky configurations. The present invention however, can be utilized in opening any number of sealed containers that do not fall into the category of envelopes, such as boxes or bags of any dimension.
In one embodiment of the present invention, the container 100 can be made from a composite sheet having a length that is sufficient to be folded over to overlap with itself to form a cavity between the folded sections of sheet, at the same time also leaving an area of sheet that is not overlapping with itself, and that extends beyond the cavity. The non-overlapping section can be used as the flap. The two edges along the length of the sheet where the sheet has been overlapped on itself are bonded to one another to produce the cavity therebetween. The need to bond the sheet at the “bottom” of the container is eliminated because folding the sheet at this location produces a closed bottom without the need for bonding. However, it is to be appreciated that the container can be made by bonding two distinct panels of sheet, wherein one sheet is slightly longer than the other sheet so as to form a flap. In this instance, the two sheets would require bonding at the “bottom” of the container. Suitable materials from which the container 100 is made include synthetic and natural materials. Low density polyethylene, linear low density polyethylene, high density polyethylene, cast polypropylene, Kraton/polypropylene blends, wood pulp are materials for making the container 100.
Referring to
In one embodiment of the container 100, the composite sheet is made from two films 140, 142, wherein each film 140 and 142 is in turn made from three layers of co-extruded polyethylene film material. It is to be appreciated that any number of films can be used to make the composite sheet as well as using any number of layers to make each film. With co-extruded polyethylene film, it may be difficult, if not impossible, to discern the boundaries between layers after co-extruding the polyethylene into a film. As can be seen in
In one embodiment of the container 100, one film can be opaque and one film can be translucent. The opaque film will usually be utilized for the exterior of the container 100. The opaque film is shown in
Still referring to
Referring to
With reference to
In one embodiment of the invention, perforations 110 or score lines may be added to the translucent polyethylene film 140 prior to the formation of the dimples and prior to bonding with the opaque film 142. While perforations 110 will extend completely through the thickness of the translucent film 140, it should be noted that once the translucent film 140 and the opaque film 142 are bonded to each other into a composite sheet, the composite sheet will have non-penetrating perforations 110 that partially extend into the thickness of the composite sheet thickness because the opaque film 142 has not been perforated. According to the invention, the creation of a flap 104 that is perforated partially into its thickness, will nevertheless, allow the flap 104 to tear along a defined narrow flap section and will be stronger and more resistant to tearing inadvertently than if perforations are cut through the entire flap thickness. According to the invention, any closure for a container can be provided with non-penetrating perforations that extend across the closure and partially into the thickness of the closure to enable the tearing of the closure and the opening of the sealed container.
Referring to
Referring now to
Referring now to
An alternate embodiment of the present invention is tape that has non-penetrating perforations to both close and open a container wherein the container does not need to include an adhesive for bonding the flap to the container body, and also does not include any non-penetrating perforations on the flap because the tape can be used to both close and open the container. A tape, according to the present invention, can be constructed that has a first and a second film, wherein one film has been provided with penetrations that completely extend through the thickness of the one film but not the second film. The file with perforations can be narrower than the film without the perforations. An adhesive layer can be added to one or the other film, wherein the adhesive can be used to close a container. Thus, the tape can be used as a means of closing the container and as a means for opening the container, wherein the means for closing the container includes the adhesive that has been applied to the film; and the means for opening the container is the two or more rows of non-penetrating perforations on one of the films. Once the tape with non-penetrating perforations has been applied to close the container, the tape provides for a way of opening the container by tearing a strip of tape that is bounded by any two rows of non-penetrating perforations.
The tape is not integral to any container, but is a separate product, and may be used to close and open containers. For example, a bag opening can be closed with a tape with non-penetrating perforations which can then be used to open the bag.
While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.
Claims
1. A container, comprising:
- a container body defining a cavity; and
- a tearable flap connected to the container body, the flap comprising one side having areas of reduced thickness defined in a row or line approximately from length's end to length's end of the flap, and the second side having a continuous film material forming the second side of the flap.
2. The container of claim 1, comprising a tearable flap formed from a first and a second film, wherein the first film has perforations that extend completely through the thickness of the first film that form the non-penetrating perforations in the flap when bonded to the second film that does not have perforations.
3. The container of claim 1, comprising a tearable flap with a plurality of score lines from length's end to length's end of the flap.
4. The container of claim 1, comprising a tearable flap with a plurality of rows of non-penetrating perforations from length's end to length's end of the flap.
3. The container of claim 1, further comprising an adhesive strip approximately from length's end to length's end of the flap.
4. The container of claim 1, further comprising an adhesive strip approximately from length's end to length's end of the flap and a cover strip on the adhesive strip.
6. The container of claim 1, comprising a tearable flap formed from at least two films, wherein each film is formed from a plurality of layers.
7. The container of claim 1, comprising a tearable flap formed from at least two films, wherein each film is a three layer co-extruded polyethylene film.
8. The container of claim 1, comprising a tearable flap formed from a first and a second film, wherein the first film is translucent and the second film is opaque.
9. The container of claim 1, further comprising at least two rows or lines of areas of reduced thickness and a pair of nicks at either end of the flap, wherein the nick ends are within the boundaries of the rows or lines of areas of reduced thickness.
10. The container of claim 1, comprising means for tearing the flap, said means including two or more rows or lines along which non-penetrating perforations or score lines are aligned from length's end to length's end of the flap, wherein the tearable flap does not have any strings, tear strips or tapes to assist with tearing the flap.
11. The container of claim 1, wherein the flap is made from polyethylene.
12. The container of claim 1, wherein the flap is made from a wood pulp product.
13. The container of claim 1, wherein the flap is made from a synthetic or natural material.
14. The container of claim 1, wherein the container is an envelope or a box.
15. A method for making a container with a tearable flap, comprising:
- bonding a first film to a second film to produce a composite sheet,
- folding the composite sheet, and bonding the overlapping edges to form a cavity from the sheet and leaving a section of non-overlapping sheet that extends beyond the cavity to form a flap therefrom, wherein the flap includes non-penetrating perforations approximately from length's end to length's end of the flap.
16. The method of claim 15, further comprising applying an adhesive strip on the flap and across the flap approximately from length's end to length's end of the flap.
17. The method of claim 16, further comprising applying a cover strip to the adhesive strip.
18. The method of claim 15, comprising making perforations in the first film but not the second film, wherein the perforations extend completely through the thickness of the first film and after bonding the first film to the second film, the perforations in the first film are the non-penetrating perforations in the flap.
19. The method of claim 15, further comprising forming dimples in the first film.
20. The method of claim 19, further comprising bonding a third film to the first film so that the third film is bonded to the convex side of the dimples.
21. The method of claim 15, comprising two or more rows along which the non-penetrating perforations are approximately aligned with from length's end to length's end of the flap.
22. A method for making a container with a tearable closure, comprising:
- forming a container with a tearable closure, wherein on a first side the tearable closure comprises non-penetrating perforations or score lines across the tearable closure, and on the second side the tearable closure comprises continuous film material.
23. The method of claim 22, wherein the container with a tearable closure is an envelope, box or bag.
24. The method of claim 22, wherein the tearable closure is a flap, lid or tape.
25. The method of claim 22, comprising bonding a first film to a second film to produce a composite sheet, folding the composite sheet, and bonding the overlapping edges to form a cavity from the sheet and leaving a section of non-overlapping sheet that extends beyond the cavity to form a closure therefrom, wherein the closure includes non-penetrating perforations or score lines across the closure.
26. The method of claim 25, comprising making perforations in the first film but not the second film, wherein the perforations extend completely through the thickness of the first film and after bonding the first film to the second film, the perforations in the first film are the non-penetrating perforations in the closure.
27. The method of claim 22, wherein the tearable closure comprises two or more rows of non-penetrating perforations aligned along the rows and across the tearable closure
28. A tearable closure for opening a sealed container, comprising:
- rows of non-penetrating perforations or score lines in and across the tearable closure on a first side; and
- continuous film material on a second side of the tearable closure.
29. The tearable closure of claim 28, wherein the tearable closure is a flap, lid or tape.
30. The tearable closure of claim 28, wherein the tearable closure comprises a first and a second film, wherein the first film has perforations that extend completely through the thickness of the first film, and the second film does not include perforations so that the perforations in the first film are the non-penetrating perforations in the closure.
31. The tearable closure of claim 28, comprising two or more rows of non-penetrating perforations aligned along the rows and across the tearable closure.
32. A container with a tearable closure, comprising:
- a container body defining a cavity; and
- a tearable closure comprising rows of non-penetrating perforations or score lines in and across the tearable closure on a first side, and continuous film on a second side of the tearable closure.
33. The container of claim 32, wherein the container is an envelope, box or bag.
34. The container of claim 32, wherein the tearable closure is a flap, lid, or tape.
35. The container of claim 32, wherein the container is an envelope and the tearable closure is a flap.
36. The container of claim 32, wherein the tearable closure comprises a first and a second film, wherein the first film has perforations that extend completely through the thickness of the first film, and the second film does not include perforations so that the perforations in the first film are the non-penetrating perforations in the closure.
37. The container of claim 32, comprising two or more rows of non-penetrating perforations aligned along the rows and across the tearable closure.
38. A container, comprising:
- a container body defining a cavity; and
- a tearable flap connected to the container body, wherein the flap comprises non-penetrating perforations approximately from length's end to length's end of the flap wherein the flap comprises a first translucent film and a second opaque film, the first translucent film has perforations that extend completely through the thickness of the first translucent film and the second opaque film does not have perforations so that the perforations in the first translucent film are the non-penetrating perforations in the flap, the flap comprising two or more rows along which the non-penetrating perforations are approximately aligned with from length's end to length's end of the flap.
39. A container comprising at least two rows of non-penetrating perforations in the container, wherein the rows are substantially parallel to each other.
40. The container of claim 39, wherein the rows are along an edge of the container.
Type: Application
Filed: Apr 13, 2004
Publication Date: Oct 13, 2005
Patent Grant number: 8562216
Inventors: Brian Kendall (Maineville, OH), Murray Fullerton (Papakura)
Application Number: 10/823,080